Skip Navigation

Pro-Ject Tube Box S

Vacuum tube phono preamplifier for moving magnet and moving coil cartridges

12 Reviews | 1 question - 5 answers

Item # 252TUBXSB

This item is no longer available.

Shop all Phono Preamps


Our take on the Pro-Ject Tube Box S

Experience the vacuum tube difference

Few things go together quite like the relaxed sound of vinyl and the warm glow of vacuum tubes. Pro-Ject understands. They've been building high-performance turntables and electronics for years. Their Tube Box S phono preamp is a shining example of all that expertise. Connect it to your 'table, and this sweet little tube preamp will lend depth and spaciousness to the sound of your LPs. It's an addictive experience that will keep you listening deep into the night.

A big upgrade from stock turntable inputs

Many receivers and amplifiers these days lack the phono input you need to hook up your turntable. And when manufacturers do include one, they often use low-cost, low-performance circuitry that sounds lifeless and flat. Pro-Ject's Tube Box S neatly solves that problem. It boosts and equalizes the tiny voltages generated by your 'table's phono cartridge to deliver a robust, line-level signal infused with detail and three-dimensional presence. Pro-Ject's dual-mono design dedicates one tube per channel for maximum channel separation and superior stereo imaging.       

Flexible operation

This preamp's inputs are compatible with either moving magnet or moving coil cartridges, to ensure proper matching with virtually any turntable and cartridge combination. And no matter what kind of phono cartridge you mount on your turntable, this versatile preamp gives you a range of input impedance/capacitance and gain settings to optimize its performance with your system. The Tube Box S also includes a subsonic filter to reduce low-frequency turntable rumble that can result in wasted amplifier power.

Product Highlights:

  • dual-mono design using two dual-triode ECC83 (12AX7) vacuum tubes for optimal channel separation
  • compatible with moving magnet and moving coil phono cartridges
  • audiophile-grade polypropylene WIMA capacitors
  • adjustable input impedance/capacitance and gain settings for more accurate cartridge matching
  • subsonic filter to reduce low-frequency rumble and wasted amplifier power (-12dB at 20 Hz, non-switchable)
  • all-metal chassis for improved shielding from vibration and electromagnetic interference
  • external power supply for reduced noise and interference
  • gold-plated RCA connectors for corrosion-free signal transfer
  • signal-to-noise ratio: 84dB (MM), 67dB (MC)
  • THD: 0.01% (MM); 0.05% (MC)
  • RIAA response accuracy: 0.4dB (20-20,000 Hz)
  • gain: 40dB (MM), 60dB (MC)
  • 4-1/16"W x 2-15/16"H x 6-1/16"D
  • warranty: 2 years
  • Our 60-day money-back guarantee

awesome little piece....

Anonymous, Dallas, GA

What's in the Box:

  • Turntable (MM/MC) tube pre-amplifier
  • AC power adapter (with attached 5' DC cord)
  • 3 AC plug inserts (US/EU/UK)
  • Instructions For Use

Pro-Ject Tube Box S Reviews

Average Customer Review(s):

(12 Reviews)

Pro-Ject Tube Box S

Anonymous from Dallas, GA on 6/4/2017

Crutchfield Customer Review (What's this?)

awesome little piece....



Pro-Ject Tube Box S

Jerry from Fredericksburg, TX on 4/7/2017

Crutchfield Customer Review (What's this?)

Nice small amp for hooking my turntable to my Bose lifestyle 38 system. Nice sound but very little documentation for people that are not electronic engineers.

Pros: nice sound, small footprint,

Cons: poor documentation

Crutchfield response on 4/10/2017 Jerry, whenever you need help with anything you purchase from Crutchfield, please contact our tech support team right away. They can help get your gear set up and and working! Lifetime tech support comes with every Crutchfield purchase.

Pro-Ject Tube Box S

Anonymous from Marine City, MI on 3/20/2017

Crutchfield Customer Review (What's this?)

If not for the badly written and illustrated manual I'd have rated it 5 stars. After figuring out how to move the minuscule switches (and realizing that the on/off positions are opposite what appears in the diagrams) I found a good setting for my cartridge (Grado Reference Sonata l). The Tube box S performs beautifully and is an excellent match for my Rogue Audio Perseus Magnum (tube except for phono stage).



Vinyl sound at last!

Rafael P from San Juan, PR on 7/9/2016

Crutchfield Customer Review (What's this?)

I was somewhat dissatisfied with the sound of my Project Debut Carbon playing through another phono preamp. This gave me the sound I was looking for. Balanced sound, great instrument separation and that touch of warmth for long listening sessions. A good phono amp is very important in analog playback. Highly recommended!



Pro-Ject Tube Box S

Julius from brooklyn, NY on 3/28/2016

I sold everything I had and I had a lot taking to much space and I bought Bowers & Wilkins 804 D3, Bowers & Wilkins 1500 w sub, McIntosh MAC6700 receiver, Clear Audio TT with Virtuoso MM cartridge, SACD Marantz and Audioquest cables. Everything is fine with the exception of the built -in phono preamplifier. I added this tube box and now I can't be more happier. Actually I also got another Pro-Ject tube phono preamp but I personally don't see a difference.

Pros: quality, sound, design, price.

Cons: none

Transformative Addition to My System

Tripper from McKinney,Texas on 4/3/2015

Crutchfield Customer Review (What's this?)

My turntable is located in my Media Room with a cable run of approx. 60 feet to the equipment closed...not an ideal setup. Performance was OK, but lacked in just about every area, so much so I preferred my digital 96/24 recordings to a most of my vinyl. Well, that is no longer the case. It is like getting a new system for the price of the preamp. Everything is incredibly better. Depth, Detail, Warmth, Soundstage, all are so vastly improved you cannot believe it is not an entirely upgraded system. Now...what difference would this make on a more 'normal' cable run...I don't know, but I can't help but believe it would improve the sound, though maybe not as dramatically as it did with my setup. I love this preamp and would definitely recommend it.

Pros: Solid Construction, Incredible Performance, Selectable DIP switches on the bottom of the unit so you can 'match' it to your cartridge.

Cons: None...

Pro-Ject Tube Box S

Dave M from Dallas, TX on 9/18/2014

Crutchfield Customer Review (What's this?)

Recently upgraded to a Denon AVR-X4000 and was disappointed with the sound from the receiver's phono input. Almost didn't go with this as there was a one star review, however, I found this preamp does an excellent job. Love the sound now out of the new receiver, very expansive. I will say, I do have a Pro-Ject turntable and the preamp has special settings just for their gear so maybe it works better with their own brand but I found the sound to be stellar.



Tube Box S

DonC from Houston,TX on 9/3/2014

Crutchfield Customer Review (What's this?)

Was incredibly reluctant to plop down this much money on a phono pre-amp. I had purchased a new Rega 2 with AdCom cartridge 28 years ago. Within 6 months I had my first child and it was time for the turntable to go to the closet - flash forward kids are gone and it was time to break out the Rega and at the same time caught a great deal from Crutchfield on the Marantz SR7007. I have about 500 LP's dating from my first Three Dog Night and all in very good condition but there was always a little bit of what I would call background noise despite the full audio range of vinyl. So I had the Rega serviced and decided I would explore phono preamps and was instantly interested the Tube Box S as a result of the tubes as I happen to play guitar. Read all of the reviews and took the plunge despite my reservations over the price. End result for me is it is spectacular. Running thru the Marantz and Golden Ear Triton 7's and an SVS sub. Your mileage may vary.

Pros: In my opinion expands the sound palette remarkably. On my system tremendous pickup in gain and expansion of all sound ranges and on everything from Classical to Bossa Nova to jazz , hard rock, folk, metal you name it.

Cons: Obviously price - seems high. At $300 to me would be a fairer price.

Not Good IMO

Skynyrd77 from Mill creek,in on 12/8/2013

Crutchfield Customer Review (What's this?)

I don't like anything about this phono pre. It is gainless,flat and lifeless sounding . I will be sending this back. Very disappointed had high hopes .

Pros: None

Cons: All

Project Tube Box S VS, NAD PP2

Anonymous from New Paltz, NY on 11/9/2013

Crutchfield Customer Review (What's this?)

I recently upgraded my system to an NAD 757 Receiver, Synchrony 1 speakers and a VPI Turntable with a Ortofon 2M Black cartridge. I mention all this because I think the total system will impact which pre amp is best for your system. I had an NAD PP2 pre amp for several years and felt maybe that was the last weak link in my system so I upgraded to the Pro-Ject Tube Box S using Crutchfield gift credits from buying the Synchrony speakers. Yeah Crutchfield! The Project Tube Box is a beautiful pre amp but contrary to the other review in this thread I found the NAD PP2 to be have much more presence a more "open" sound. Very different sound between the 2 pre amps. The Project was 2 dimensional while the NAD in my application was 3 dimensional and filled the room with sound. If you have an issue with a strident sound or need the tube warmth the Project may be a better choice. My system is very warm on its own and I really missed the space and openess of the NAD PP2 when I tried the Project Tube box. It may depend on the application, there is definitely a big difference, but for me the NAD was the better choice. I still gave the Project 5 stars because in the right application I think it may be an excellent choice.

Pros: Warm Tube sound..looks cool and is well made.

Cons: Didn't have the presence my NAD PP2 has.

Pro-Ject Tube Box S

Anonymous from Austin, TX on 4/15/2013

Crutchfield Customer Review (What's this?)

A good sounding phono preamp. I'm not sure it's as "tubey" sounding as I would like, but it's definitely an improvement over my NAD preamp. It's also a nice looking piece of equipment to display next to the turntable.



Pro-Ject Phono Pre-amp

LarryM from Rochester, NY on 1/30/2013

Crutchfield Customer Review (What's this?)

Replaced an old, inexpensive phono pre-amp with this one. The sound quality is outstanding. My Marantz table and speakers have never sounded better.

Pros: Improved sound quality of my vinyl music portfolio.

Cons: None to date


Hands-on research

Product Research


Tube Phono Preamp (MM/MC): The Pro-Ject Audio Systems Tube Box S for MM and MC is a very high-quality phono cartridge preamplifier. This unit produces a lively and powerful performance with convincing sound staging and emotional presentation.

Metal Case: The phono preamplifier features a metal case that shields the electronics from vibration and electromagnetic interference.

Dual-Mono Circuitry: The Pro-Ject Tube Box S utilizes dual-mono architecture with two double triode tubes (12AX7A -ECC83) for optimum channel separation.

MM/MC Compatible: The Pro-Ject Tube Box S phono preamplifier offers amplifications and RIAA equalization for MM and MC cartridges.

Subsonic Filter: There is a Subsonic filter selection switch located on the rear of the unit. The Subsonic filter helps to reduce low-frequency rumble and wasted amplifier power.

Gold-Plated RCA Connections: The Pro-Ject Box S is equipped with a pair of gold-plated RCA connections for the output stage and input stage. The gold-plate RCA connectors offer corrosion-free signal transfer.

Power Requirements: The Pro-Ject Tube Box S turntable preamplifier operates off of standard household current using the included external power supply. The outboard power supply helps reduce noise and interference.

  • Input: 100-240V~50/60Hz, 0.4A
  • Output: 18V AC, 1.0A.

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

Need a phono preamp as the Anthem AVM 60 does not have one where my Marantz 8802A does. [ Mike  Jun 02, 2017 ]
Wanted to upgrade Pre-amp, came highly recommended. [ Patrick  Dec 14, 2016 ]
Tubes are neat, can't afford a full size tube amp. [ Rufus  Jul 14, 2016 ]
Highly rated around the web. [ Brian  May 01, 2016 ]
Tube sound [ David  Dec 09, 2015 ]

1 question already asked

There is one set of RCA inputs (for turntable) and one set of RCA outputs on the back, plus a post for the grounding wire. [ Rufus  Dec 11, 2015 ]
It has the in/out rca jacks in the rear. The turntable goes to the in jacks and the tube box s out jacks go to your receiver. Don't use the phono in jacks on your receiver use an aux or some other analog in, [ Billy  Dec 11, 2015 ]
Yes rca cables from turn table to the box then from box to receiver. a lot of new receivers do not have a phono input on them and you have to use a box like this. [ Craig  Dec 11, 2015 ]
There are in & out RCA jacks. You would not use the phono input on your receiver since that input contains a pre-amp, instead you would use another RCA input such as a cd input. [ Thomas  Dec 11, 2015 ]
yes 1 set in 1 set out. This is for an amplifier without a phono amplifier, so to be safe, I would plug into an aux. So out from the turntable into the Turntable amp, and out to the receiver [ James  Dec 11, 2015 ]